cdp enhancement

[wangjj9219]

1. support use lp token as collateral
2. provider call for pre-issuing stable coin to obtain more collateral and deposit into CDP, the collateral ratio will decrease.
3. provider call for selling collateral in CDP to obtain stable coin to repay debit, the collateral ratio will increase.

[codecov]

Codecov Report

Merging #1886 (45adbef) into master (0c089fa) will increase coverage by 0.60%.
The diff coverage is 90.98%.

@@            Coverage Diff             @@
##           master    #1886      +/-   ##
==========================================
+ Coverage   85.31%   85.91%   +0.60%     
==========================================
  Files          82       79       -3     
  Lines       17934    18696     +762     
==========================================
+ Hits        15300    16063     +763     
+ Misses       2634     2633       -1     

Impacted Files	Coverage Δ
modules/honzon/src/lib.rs	70.78% <0.00%> (-17.95%)	⬇️
modules/incentives/src/lib.rs	81.95% <ø> (ø)
modules/support/src/lib.rs	16.39% <0.00%> (-0.56%)	⬇️
modules/cdp-engine/src/lib.rs	74.95% <83.33%> (+4.09%)	⬆️
modules/dex/src/lib.rs	81.87% <86.00%> (+2.25%)	⬆️
modules/cdp-treasury/src/lib.rs	85.71% <88.88%> (+0.18%)	⬆️
modules/cdp-engine/src/tests.rs	99.81% <100.00%> (+0.09%)	⬆️
modules/cdp-treasury/src/tests.rs	100.00% <100.00%> (ø)
modules/loans/src/lib.rs	88.09% <100.00%> (+0.29%)	⬆️
modules/loans/src/tests.rs	100.00% <100.00%> (ø)
... and 12 more

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[wangjj9219]

@qwer951123 @nnnnnnnnnni This pr contains changes about events related to collateral auction and loan position. Data services should be compatible with these changes.