IndFarmCost 0.1.0

• Initial CRAN submission.
• Implements Indian farm cost concepts A1, A2, B1, B2, C1, C2, and C3.
• Adds farm-level and grouped cost analysis, returns, cost shares, break-even analysis, cost of production, sensitivity analysis, summaries, and plotting.
• Includes a reproducible example dataset, tests, vignette, README, and citation.