Re-added original .gitignore back to secp256k1 folder.
Re-added original .gitignore back to secp256k1 folder.

EclipseCrypto/eclipse,EclipseCrypto/eclipse,EclipseCrypto/eclipse,EclipseCrypto/eclipse,EclipseCrypto/eclipse,EclipseCrypto/eclipse,EclipseCrypto/eclipse