feat: loan classification doctype and IRAC provisioning conf table and 'asset' cleanup

[anandbaburajan]

• Added new Loan Classification doctype and IRAC Provisioning Configuraton table in the company master
• Updated Loan Asset Classification Range table to use the above Loan Classification doctype
• Renamed Process Loan Asset Classification -> Process Loan Classification
• Renamed Loan Asset Classification Range -> Loan Classification Range
• Added temporary collection_offset_sequence_for_written_off_asset
• Removed 'asset' from all loan related fields (except collection_offset_sequence_for_standard_asset, collection_offset_sequence_for_sub_standard_asset and collection_offset_sequence_for_written_off_asset since they'll be restructured anyway later)

[codecov-commenter]

Codecov Report

Merging #18 (91ee3e0) into develop (c7df023) will increase coverage by 0.11%.
The diff coverage is 96.42%.

@@             Coverage Diff             @@
##           develop      #18      +/-   ##
===========================================
+ Coverage    49.24%   49.35%   +0.11%     
===========================================
  Files           44       46       +2     
  Lines         2646     2652       +6     
===========================================
+ Hits          1303     1309       +6     
  Misses        1343     1343              

Files Changed	Coverage
lending/hooks.py	ø
lending/install.py	ø
lending/loan_management/doctype/loan/loan.py	90.00%
...doctype/loan_classification/loan_classification.py	100.00%
..._classification_range/loan_classification_range.py	100.00%
...onfiguraton/loan_irac_provisioning_configuraton.py	100.00%
...anagement/doctype/loan_repayment/loan_repayment.py	100.00%
...loan_classification/process_loan_classification.py	100.00%