sap_system_facts: Add SID and permission check to facts module

[marcelmamula]

Changes

• Add permission check for /usr/sap/hostctrl/exe/sapcontrol and module fail if missing. This is important for non-root users
• Add permission check for HANA and NW folders, which will not fail but skip either SID or Instance
• Add SID pattern check to ensure we check only correct pattern
• Add Instance name pattern check to skip folders like SYS, exe, hdbclient

Idea for permission check comes from @zoliton in #70, but it is applied to all folders with better accuracy, not just root folders.

Tests

Tested on BW4HANA system on SLES_SAP 16.0.

User Ansible with no permission to execute sapcontrol

fatal: [b01hana]: FAILED! =>
    changed: false
    msg: 'Permission denied: Ansible user cannot execute /usr/sap/hostctrl/exe/sapcontrol'

User Ansible with no permissions to folders

ok: [b01hana] =>
    __sap_system_facts_output:
        ansible_facts: {}
        changed: false
        failed: false
        msg: No running SAP instances found or Ansible user cannot access them.

User Ansible with access only HANA instance:

ok: [b01hana] =>
    __sap_system_facts_output:
        ansible_facts:
            sap:
            -   InstanceType: HANA
                NR: '90'
                SID: H01
                TYPE: HDB
        changed: false
        failed: false
        msg: SAP System facts were collected.

User root

ok: [b01hana] =>
    __sap_system_facts_output:
        ansible_facts:
            sap:
            -   InstanceType: HANA
                NR: '90'
                SID: H01
                TYPE: HDB
            -   InstanceType: NW
                NR: '00'
                SID: B01
                TYPE: ASCS
            -   InstanceType: NW
                NR: '01'
                SID: B01
                TYPE: PAS
            -   InstanceType: NW
                NR: '11'
                SID: B01
                TYPE: PAS
        changed: false
        failed: false
        msg: SAP System facts were collected.

[marcelmamula]

Tested and confirmed by #70 (comment)

[sean-freeman]

LGTM - good approach and good first contribution from @zoliton